CS5127 Datasheet | Cherry Semiconductor Corporation

Description The CS5127 is a fixed frequency dual output nonsynchronous buck controller. It contains circuitry for regulating two separate outputs. Each output channel contains a high gain error amplifier, a parator and latch, and a totem-pole output driver capable of providing DC current of 100m A and peak current in excess of 0.5A. A mon oscillator controls switching for both channels, and a sync lead is provided to allow parallel supply operation or shifting of the switching noise spectrum. An on-chip 5V reference is capable of providing as much as 10m A of current for external circuitry. The CS5127 also contains two undervoltage lockout circuits. The first lockout releases when VIN reaches 8.4V, while the second lockout ensures that VREF is higher than 3.6V. The outputs are held in a low state until both lockouts have released. The controller is configured to utilize the V2ª control method to achieve the fastest possible transient response and best overall regulation. This dual controller is a cost-effective solution for providing VCORE and VIO power solutions in puting applications using a single controller. The CS5127 will operate over an input voltage range of 9.4V to 20V and is available in a 16 lead wide body surface mount package. Features s Nonsynchronous Buck Design s V2ª Control Topology s 100ns Transient Loop Response s Programmable Oscillator Frequency s 30ns Typical Gate Rise and 10ns Fall Times (No Load) s Frequency Synchronization Input s ENABLE Input Controls Channel 2 Gate Driver s 5V/10m A Reference Output Applications Diagram 12V, 5V to 2.8V @ 7A and 3.3V @ 7A for 233MHz Pentium¨ Processor with MMXª Technology 5V + Q1 FMMT2222ACT SYNC CT VIN VREF Package Option +5V 12V C3 + 1m F 16 Lead SOIC Wide SYNC CT C1, C2 2 x 680m F C4, C5 2 x 680m F + VIN VREF ENABLE VFB2 P2 VFFB2 GATE2 PGND C9 0.1m F + C8 1m F Q3 IRL3103S D2 1N5821 R1 20k C6 0.1m F ENABLE VFB2 P2 VFFB2 GATE2 PGnd VFB1 P1 C7 330p F R2 27k L1 Q2 IRL3103S D1...